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act

v. · n.
US //ˈækt// UK //ˈækt// act
  1. 1 to do something (v.)
    A1 Beginner

    to take action or do something for a specific reason.

    to take action or exert energy in order to achieve a specific result. Often used intransitively.

    Example

    The police had to act quickly to stop the thief from escaping.

    Example

    The emergency services must act decisively when a natural disaster strikes to minimize the loss of life and property.
  2. 2 theatre/film (v.)
    A2 Elementary Theatre

    to perform a part in a play, movie, or television show.

    to perform a fictional role in a dramatic production. Can be used transitively with a role as the object or intransitively.

    Example

    She has wanted to act in a Hollywood movie since she was a child.

    Example

    He was chosen to act the part of the protagonist because of his ability to convey complex emotions without speaking.
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  1. 3 to behave (v.)
    B1 Intermediate

    to behave in a particular way.

    to conduct oneself or behave in a specified manner, often temporarily or falsely.

    Example

    Stop acting like a child and help me clean the kitchen.

    Example

    The suspect began acting suspiciously as soon as the investigators mentioned the missing documents.
  2. 4 a deed or thing done (n.)
    A2 Elementary

    something that someone does.

    a single thing done; a deed or action.

    Example

    Giving her seat to the elderly man was a kind act.

    Example

    The charity described the donation as a selfless act of generosity that would fund the project for a year.
  3. 5 a law (n.)
    B2 Upper Intermediate Formal Law

    a law that has been officially passed by a government.

    a formal decision or law passed by a legislative body. Often capitalized when referring to a specific law.

    Example

    The new Act of Parliament will change how taxes are collected.

    Example

    The Clean Air Act was introduced to regulate industrial emissions and improve public health in urban areas.
  4. 6 part of a play (n.)
    B1 Intermediate Theatre

    one of the main parts that a play or opera is divided into.

    a major division of a dramatic work, such as a play, ballet, or opera.

    Example

    The hero doesn't appear until the second act of the play.

    Example

    The tension builds throughout the first act, culminating in a dramatic confrontation just before the intermission.
  5. 7 a performance or show (n.)
    B1 Intermediate Theatre

    a short performance or a person/group that performs as part of a larger show.

    a short performance or one of several performances in a variety show or circus.

    Example

    The circus had a very funny clown act that the children loved.

    Example

    The festival organizers are still looking for a headline act to close the main stage on Sunday night.
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